We're going to turn to washington now. Abc's pierre thomas who covers the justice department. Pierre, you have been talking to your sources, any threat from this terrorist group in u.S. Reporter: Right now, our sources are saying no specific threat to the united states. But they're monitoring this very, very closely. They want to know the tactic. They're paying very close attention to that. Also, there's general concern because al shabaab has had some ties to the united states, in terms of young americans, mostly from minneapolis, minnesota, going there to hookup with radicals there. What is so alarming about this attack is that it took place in the shopping mall, which begs the question, how prepare are we here in america? Well since the mum buy attacks in india in 20008, u.S. Government have being paying attention to security in malls. They have been doing practices. They're told to have their local law enforcement patrol, higher capacity weapons in their cars so they can respond. I can recall going to an fbi training session at a local hotel in d.C., In these type of scenarios you have to go in and go in fast. U.S. Law enforcement officials have been thinking about this particular issue. Coming at times when americans go to shopping malls. Okay, pierre, thank you. As this crisis continues we want to remind you we'll have

This transcript has been automatically generated and may not be 100% accurate.

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